Thread: RRS 3.0 blowing smoke (lots of it)

Originally Posted by GregMilner

Graeme thanks for that...could well be. I'm sure it was the secondary turbo they replaced. I also assumed the primary turbo stopped spinning once the secondary one took over. Obviously not. I'll take it back to the dealer and take them for a drive.

I'm no expert at all but there are different set ups for twin turbo engines for whatever reason.

My Merc sedan is a twin turbo but it has a bypass that shuts down the primary and fires up the secondary at a pre-determined rev range.

I think the V8 twin in the RR is another set up again. I don't know what Toyo do with their V8 diesel.

What's the term?...serial and parrallel...variable and fixed geometery/vein......and I guess there are combo's of something in between.

I've read that the D4 primary turbo pushes through the secondary and then feeds the secondary once it hits it's optimum rev range. Physically I have no idea how that works and would love a comprehensive description and maybe a few stick drawings . I have ideas about how that might work but can't claim anything further than ideas.

I've gone through the turbo replacement and was led to believe it's the fact that in the first build D4's (and I guess RR with the same engine) that the secondary turbo would not get worked often enough or hard enough, causing a build up of oil, then causing over pressurisation...which actually means it failed to deal with this issue...a design flaw!

Meant to add, it's strange that the same engine produces so many different symptoms. My 3.0l, even with a dodgy turbo has never blown smoke or consumed oil.

Cheers.

We videoed the the problem from in the car with the phone

Originally Posted by FarmerBuzz

We videoed the the problem from in the car with the phone

Good idea. I'll do the same.

Haven't had a problem with my Sept 2009 build 3.0Lt D4. Must be one of the lucky ones.
You would think that if the problem was too wide spread, Landrover would do a re-call.

Cheers, Craig

The primary turbo is the larger one and does most of the work. The secondary is small and only assists higher up the range, with inlet and exhaust valves fitted to isolate it when not required. The 2nd turbo does not push air through the primary. The original s/w kept the 2nd turbo isolated until 2500 rpm (not 2900). This was very detectable during modest acceleration and also if upshifted soon after as the return to 1 turbo due to revs dropping below 2500 when still accelerating was not smooth. LR was working on having the 2nd turbo working just a little all the time to prevent the oil accumulation but I don't know if LR persisted with that change. LR now replace the 2nd turbo as the cure without any investigation, acting only on customer's reports. The primary is variable vane like the 2.7 and the secondary fixed like the TD5.

Originally Posted by Celtoid

.....I've read that the D4 primary turbo pushes through the secondary and then feeds the secondary once it hits it's optimum rev range. Physically I have no idea how that works and would love a comprehensive description and maybe a few stick drawings . I have ideas about how that might work but can't claim anything further than ideas....

Celtoid, here's an animation on the turbo workings:

[ame=http://www.youtube.com/watch?v=6oFE90_BgpM]Land Rover Discovery 4 V6 Diesel Engine - YouTube[/ame]

Originally Posted by SBD4

Celtoid, here's an animation on the turbo workings:

Land Rover Discovery 4 V6 Diesel Engine - YouTube

What a cracking animation, thanks for that.

Cheers,

Kev.

Originally Posted by Graeme

The primary turbo is the larger one and does most of the work. The secondary is small and only assists higher up the range, with inlet and exhaust valves fitted to isolate it when not required. The 2nd turbo does not push air through the primary. The original s/w kept the 2nd turbo isolated until 2500 rpm (not 2900). This was very detectable during modest acceleration and also if upshifted soon after as the return to 1 turbo due to revs dropping below 2500 when still accelerating was not smooth. LR was working on having the 2nd turbo working just a little all the time to prevent the oil accumulation but I don't know if LR persisted with that change. LR now replace the 2nd turbo as the cure without any investigation, acting only on customer's reports. The primary is variable vane like the 2.7 and the secondary fixed like the TD5.

Graeme I just spoke to the LR dealer and they tell me they replaced the turbo on the driver's side of the vehicle, which from the youtube video seems to me to be the secondary turbo, which as you say is the one they typically replace.
Still smoking (blue) like a bastard when I hit the gas.